I stopped retiring once I loomed my bow three times and loomed my arrows once. Personally since my gear only costs 11K I make money hand over fist and can easily just buy heirlooms off the market from there.
My level 33 (actually having to gun for 34 now since it is quicker then I thought) does not require the extra 2 damage since each point of power draw is 14% bonus.
However, since it takes as long to reach level 34 as it does to retire 4 times, it may be worthwhile for you to grab every loom you want first, especially if you don't make a lot of money and thus can not use the market easily.